This invention relates to an apparatus for navigating a vehicle in accordance with a course set before travel starts. More particularly, the invention relates to a system for outputting intersection distance information in a navigation apparatus which provides traffic lane information after the vehicle has turned at an intersection.
Recent years have seen extensive development of vehicular navigation systems in which a course is preset before travel starts and the driver is given course information in accordance with the preset course.
When the driver is guided along the preset course, the conventional navigation apparatus merely displays a map on the screen of a CRT and superimposes the course on the map. Accordingly, observes the course displayed on the map and decides at which intersection the next turn is to be made.
However, with the conventional arrangement in which the driver determines the intersection by observing the course on the map, the driver is constrained to read his present position, the distance to the intersection and characterizing features near the intersection from the course display while driving the vehicle, and the driver must visually identify the intersection at which the next turn is to be made. This usually requires that the driver give his utmost attention to the task of identifying the intersection. Accordingly, since the driver's concentration is focused on identifying the proper intersection, he cannot give due consideration to, and is not aware of, the manner in which the vehicle should be steered after the turn at this intersection is made. If one intersection requiring a turn immediately follows another, the vehicle must be steered into the proper lane immediately after the turn at the first intersection is made. With the conventional system, however, the driver cannot determine which is the proper lane. This can cause the driver to make a dangerous lane change or to completely pass through the second intersection without making the turn.